1. Field of the Invention
The present invention relates to an electromagnetic switch used for opening and closing a main contact of a motor circuit of a starter.
2. Description of Related Art
There is disclosed, in Japanese Patent Application Laid-open No. 2002-313205, an electromagnetic switch in use for a starter, which has a plate-like terminal that is connected to a lead wire of an excitation coil (this terminal being referred to as “50 terminal” hereinafter). This plate-like 50 terminal is pressure-fixed to a coil bobbin of the excitation coil, and its front end is led out from a mold cover through an insertion hole formed in this mold cover. A gap between the insertion hole and the 50 terminal is airtight sealed by a rubber seal member pressure-fitted to the 50 terminal.
In the conventional electromagnetic switch described above, the 50 terminal is not fixed to the mold cover. That is, since the 50 terminal is only inserted into the insertion hole formed in the mold cover through the seal member, it is difficult to suppress the 50 terminal from vibrating when the electromagnetic switch is applied with a large vibrational load. The vibration of the 50 terminal may cause the lead wire of the excitation coil connected to the 50 terminal to break. As a technique to cope with this problem, as shown in FIG. 10, it is known to use, as the 50 terminal 100, a bolt that is tightly fastened to the mold cover 120 by use of the cup washer 110 or a nut.
However, this conventional technique has a problem in that since it needs, in addition to the bolt as the 50 terminal, various parts including the cup washer 110 for fixing this bolt to the mold cover 120, the terminal 140 to which the lead wire of the excitation coil 130 is connected, and the connector 150 for electrical connection between the terminal 140 and the bolt as the 50 terminal. Besides, since the 50 terminal is a bolt, it is difficult to employ the shape of a waterproof coupler unlike the case in which a plate-like terminal is used as the 50 terminal.